Organic phosphites are known for their antioxidant properties when added to polymers and other organic materials. At least one purpose associated with the addition of a stabilizer to a polymeric resin is to prevent deterioration of the polymers derived from the resin during processing at high temperatures and also to permit the manufacture of products with increased intrinsic quality attributable at least in part to increased resistance to thermal and light degradation during their intended use.
Organic phosphites can be synthesized from variety of alcohols, diols, triols, and alkylphenols. Among them are the commercially significant phosphites, tris(nonylphenyl)phosphite (TNPP) and tris(2,4-di-t-butylphenyl)phosphite. Historically, these two phosphites have been the low cost stabilizers for the rubber and plastics industry. Recently, however, alkylphenols and phosphites made from them have come under scrutiny due to concerns about them being xeno-estrogenic and bio-accumulative. Therefore suitable replacements for these are desired.
It has been determined that many useful polyphosphites can be synthesized based on cycloaliphatic diols, e.g., cylcohexane dimethanol (“CHDM”), and which are suitable replacements for the alkylphenol containing phosphites. The phosphites made at least in part from CHDM are superior to many of the commercial phosphites in terms of performance, thermal stability, and hydrolyic stability. Furthermore a great variety of phosphites can be produced from cycloaliphatic diols (e.g., CHDM) having a variety of properties.
Therefore what is disclosed are solid and liquid polyphosphites synthesized at least in part from saturated cycloaliphatic reactants (e.g., cycloaliphatic diols), mono-hydroxy terminated alcohols acting as chain stoppers and trifunctional phosphorus moieties (e.g., triaryl phosphite) and their performance as stabilizers.